All living things need someway to obtain energy. Without energy, life can't exist. Nearly all energy on the planet gets its start with the sun. The sun releases energy and shines it onto the earth, giving us heat and light. It is then up to the green plants- the producers - to use the sunlight to make food through photosynthesis. The producers are the only living things that can make their own food. All other living things either need to eat producers, or eat things that eat producers.

The first type of consumers are called herbivores . These are animals that eat plants. They take the energy that plants made and use it for themselves. Examples of herbivores are rabbits, mice, some birds, and many insects.

The second type of consumers are omnivores . These are animals that eat both plants and animals. Humans, raccoons, and bears are good examples of omnivores. Some omnivores eat mostly plants with some animals mixed in, while other omnivores may eat mostly animals and only occasionally eat plants.

Another type of consumers are carnivores . Carnivores are animals that only eat other animals. Carnivores can eat herbivores, omnivores, even other carnivores on occasion. Examples of carnivores in Michigan are coyotes, snakes, and owls.

There's more. Whenever something dies or produces wastes, special organisms called decomposers work to break it down and turn it into useful soil. You may not think about decomposers very often, but without them, we would constantly be walking around knee-deep in dead stuff. Organisms like fungi, many types of insects, and bacteria are examples of decomposers.

So it all se ems pretty easy right? Well it can get a little more complicated. Although it may be easiest to think of the process as a simple chain of events from a single plant to a single herbivore all the way to a single carnivore, it is rarely that simple. To start with, herbivores rarely only eat a single type of plant, and carnivores rarely eat a single type of animal. Not to mention that many carnivores will also occasionally eat plants and many herbivores will sometimes eat meat if they get the chance. As a result, all different types of plants and animals are interconnected in a complex process that is often called the food web.

Most organisms rely on many other types of organisms for food. If any one type of food source disappears, it can become very difficult for other organisms to find enough food. An environment is healthiest when it has the greatest number of different kinds of organisms in it. The measure of how many different types of organisms are present in an environment is called biodiversity. The greater the biodiversity in a given environment, the less likely any one part of the food web will become extinct.